Grangier Junior, A. Wellman, F.L.

Algunos fungicidas usados con adherentes en aspersiones para cafetos jóvenes - Oct-Dic 1955

++ 9 tab. 11 ref. Sum. (En)

The use of sprays to control plant diseases is more difficult in parts of the warm tropics where rainfall is high. In the region of Turrialba, Costa Rica, the tenacity of fungicides in control of certain coffee leaf disease in nurseries, seems as important as the chemical toxicity to the fungus leaf parasites attacking seedlings. It was shown in laboratory studies, working with fungicidal compounds with stickers, and with their mixtures, that these mixtures coul be divided into the following four groups: 1) very poor adhesive qualities; 2) fair adhesive qualities; 3) medium qualities; and 4) good qualities. Of the many materials tested 12 were selected for use in the possible control of coffee leaf infections in the nursery caused by Cercospora and Colletotrichum. It was found that whenever the sticker PEPS was included in the mixtures, the control was significantly better. At first when compared with Captan or Perenox, with or without stickers, Fermate was the most effective control for the two diseases. The fungicide Crag 658 with stickers was only a little better than untreated plots. Later a new sticker compound, RDA-156-B10, was combined with Captan and gave much better results. Analysis showed the control to be as good as with Fermate Meanwhile urea bad been found good in absorption in coffee leaves. It was also proved to be compatible with the Captan-sticker mixture. The Captan-sticker-urea mixture was used as a fungicidal and nutrient spray on coffee seedlings in the nursery. Nursery that was not sprayed showed poor growth, and defoliation from leaf infections was severe. The new treatment, applied at either 3 or 4 week intervals gave good results in disease control and the urea addition was found to result in significantly better growth


COFFEA ARABICA
PLANTULAS
FUNGICIDAS
CAPTAN
ADHERENTES
CERCOSPORA COFFEICOLA
COLLETOTRICHUM COFFEANUM
ENFERMEDADES FUNGOSAS
CONTROL DE ENFERMEDADES
COSTA RICA